I did a more thorough search for bug reports in GCC and I found some existing bug reports for gfortran, namely:
- 56670 – Allocatable-length character var causes bogus warning with -Wuninitialized
- 91442 – Wrong "may be used uninitialized" warning with allocation on assignment
- 77504 – [10/11/12/13 Regression] "is used uninitialized" with allocatable string and array constructors
Full Bug List